Designation: D 1101 – 97a
Standard Test Methods for
Integrity of Adhesive Joints in Structural Laminated Wood Products for Exterior Use1 This standard is issued under the fixed designation D 1101; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A superscript superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
INTRODUCTION
The integrity of adhesive joints for structural laminated wood members, such as laminated arches and beams, should be at least equal to that of the wood. Because initial strength tests generally are not an adequa adequate te measur measuree of integr integrity ity of adhesi adhesive ve joints joints under under severe severe servic servicee condit condition ions, s, a test test that that simulates the effects of exterior exposure has been devised to evaluate adhesive joints in structural laminated wood members intended for this type of service. D 907 Terminology Terminology of Adhesives2 D 2559 Specificati Specification on for Adhesives for Structural Structural LamiLaminated Wood Products for Use Under Exterior (Wet Use) Exposure Conditions 2
1. Scope Scope 1.1 These These test test method methodss cover cover an accele accelerat rated ed means means of measurin measuring g the resistanc resistancee to delamina delamination tion of structura structurall lamilaminated wood members intended for exterior service. 1.2 These test methods methods are not intended intended as substitut substitutes es or replacements for the more severe test of resistance to delaminati nation on in Spec Specifi ifica cati tion on D 2559 2559,, whic which h is used used to qual qualif ify y adhesives for structural laminated wood products for use under exterior (wet-use) exposure conditions under industry standard ANSI/AITC A190.1-1992. 1.3 Two test methods are included. included. Choice Choice of test method method depends on purpose of the test and available time to complete. 1.3.1 Test Method A —This test requires 3 days to complete and is a method for determining the suitability of adhesives and manufact manufacturing uring technique techniquess and equipment equipment for productio production n of joints adequate for exterior service. 1.3.2 Test Method B —This test requires approximately 12 1 ⁄ 2 h. (If excessive delamination occurs, the cycle is repeated). It is a qualit quality-c y-cont ontrol rol type type test test for examin examining ing adhesi adhesive ve joint joint quality. 1.4 The values values stated in SI units are to be regarded regarded as the standard. The values given in parentheses are for information only. 1.5 This This standa standard rd does not purport purport to addre address ss all of the safe safety ty conc concer erns ns,, if any any, asso associ ciat ated ed with with its its use. use. It is the the responsibility of the user of this standard to establish appro priate safety and health practices and determine the applicability of regulatory limitations prior to use.
3. Terminology 3.1 Definitions—Man —Many y term termss in thes thesee test test meth method odss are are defined in Terminology D 907. 3.1.1 glulam, n—synonym —synonym for structural-glued-laminated timber . 3.1.2 structural-glued-laminated timber , n—an engineered stress-ra stress-rated ted product product of a timber timber laminati laminating ng plant plant comprisin comprising g assemblie assembliess of specially specially selected selected and prepared prepared wood laminations securely bonded together with adhesives, with the following lowing character characteristi istics: cs: ( 1) the the grai grain n of all all lami lamina nati tion onss is approximately parallel longitudinally; and ( 2) the laminations may be comprised of pieces end-joined to form any length, of pieces placed or glued edge-to-edge to make wider ones or of pieces bent to curved form during gluing. (Synonym glulam) ANSI/AITC ANSI/AITC A190.1-1992. A190.1-1992. American American National National Standard Standard for Wood Products, Structural Glued Laminated Timber (Edited to conform with ASTM format) 3.2 Definitions of Terms Specific to This Standard: laminated wood , n—the fabricated product resulting 3.2.1 laminated from from the bonding bonding of two or more more lamina laminatio tions, ns, with with each each lamina laminatio tion n made made from from one or more more pieces pieces bonded bonded either either lengthwise, edgewise, or both, and all with the direction of the grain grain essent essential ially ly parall parallel, el, to form form a larger larger piece such such as a structural member. member.
2. Referenced Documents
4. Significanc Significancee and Use
2.1 ASTM Standards:
4.1 The test is suitable suitable for check testing properly properly selected selected samples from regular production or for determining the suitability of adhesives and bonding techniques for the production
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These test methods are under the jurisdiction of ASTM Committee D 14 on Adhesives Adhesives and are the direct responsibilit responsibility y of Subcommittee Subcommittee D14.30 D14.30 on Wood Adhesives. Current Current edition edition approved approved Sept. 10, 1997. Published May 1998. 1998. Originally Originally published published as D 1101 – 81. Last previous previous edition edition D 1101 – 97.
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Annual Book of ASTM Standards Standards,, Vol 15.06.
D 1101 of joints for exterior service. 4.2 Vary the number of specimens taken from each member and the number of members selected for test depending on the total number of members involved and the purpose of the tests. It is advisable, however, to include at least three specimens in the test, with the specimens selected to represent the probable range of quality of the adhesive joints. 4.3 Adhesive joints at knots and knotty areas in general are not dependable under severe exposures. Disregard development of delamination at knots and do not include in the measurements or calculations.
15 %, in an oven capable of maintaining 45 to 50 air changes per minute when the oven is empty. During drying, place the specimens at least 50 mm (2 in.) apart with the end-grain surfaces parallel to the stream of air. Repeat the entire soaking-drying cycle twice to comprise a total test period of 3 days. 7.2 At the end of the final drying period, measure to the nearest 0.05 in. (1.3 mm) the total length of open adhesive joints (delamination on the end grain surface of the specimens). Do not regard failure in the wood due to checking or other causes as delamination (see Note 1). Ignore isolated delamination less than 2.5 mm (0.10 in.) long and more than 5.1 mm (0.20 in.) away from the nearest delamination.
5. Apparatus 5.1 Autoclave—An autoclave or similar pressure vessel designed to safely withstand pressures of at least 517 kPa (75 psi) is required for impregnating the specimens with water. Equip the pressure vessel with a vacuum pump or similar device capable of drawing a vacuum of at least 635 mm (25 in.) Hg (at sea level) in the vessel, and a pump or similar device for obtaining pressure of at least 517 kPa (75 psi) (gage pressure).
NOTE 1—Delamination is a term used to express separation of the wood surfaces at the adhesive joints. When the separation is in the wood, even though very close to the adhesive joint, it is termed wood failure or checking. Magnification is often necessary to determine whether the failure is in the adhesive or in the wood. A feeler gage 0.08 to 0.10 mm (0.003 or 0.004 in.) in thickness is convenient for probing into the joint to determine if separation actually exists. A circular fluorescent desk lamp with 53 viewing magnifier in the center of the lamp has been found to work well and aid in these determinations.
6. Test Specimens 6.1 Prepare or select the test specimens in such a manner that they are representative of the production run. When the test is employed to investigate new adhesives and procedures, ensure that enough specimens are available to cover fully the variables under study. 6.2 Take each test specimen from a full cross-section of the laminated member to be tested. Prepare by cutting perpendicular to the grain of the wood, 76 mm (3 in.) in length (along the grain). Cut the end-grain surfaces of the specimen with a sharp saw or other tool that produces a smooth surface. 6.3 Ensure that each test specimen is representative of all the bond lines but need not necessarily include all, and that each test specimen is at least 152 mm (6 in.) in depth, or the full depth of section if less than 152 mm (6 in.) deep. 6.4 Vary the number of specimens taken from each member and the number of members selected for test, depending on the total number of members involved and the purpose of the tests. It is advisable, however, to include at least three specimens in the test, with the specimens selected to represent the probable range of quality of the adhesive joints.
TEST METHOD B 8. Procedure 8.1 Weigh and record to the nearest 1 g (0.002 lb) the weight of each test specimen. Place the test specimens in the autoclave or pressure vessel and weight them down. Admit water, at a temperature of 18 to 29°C (65 to 85°F) in sufficient quantity so that the specimens are completely submerged. Separate the test specimens by stickers, wire screens, or other means in such a manner that all end-grain surfaces are freely exposed to the water. Draw a vacuum of 508 to 635 mm (20 to 25 in.) Hg (at sea level) and hold it for 30 min. Then release the vacuum and apply a pressure of 517 6 34 kPa (75 6 5 psi) for 2 h. Dry the specimens for a period of approximately 10 h at 71°C (160°F) in an oven capable of maintaining 45 to 50 air changes per minute when the oven is empty (see Note 2). During drying, place the test specimens at least 50 mm (2 in.) apart with the end grain surfaces parallel to the stream of air. NOTE 2—The relationship between the air temperature and the wet bulb reading yields an approximate relative humidity of 8 to 10 % and corresponds to a wet bulb depression of 70°F or 39°C.
TEST METHOD A
8.2 The actual time in the drying oven is controlled by the weight of the test specimens. When their weight has returned to within 15 % of the original test specimen weight prior to the beginning of the test, delamination is then observed and recorded. 8.3 Measure to the nearest 1.3 mm (0.05 in.) the total length of open adhesive joints (delamination) on the end-grain surfaces of the specimens. Do not regard failure in the wood due to checking or other causes as delamination (see Note 1). Ignore isolated delamination less than 2.5 mm (0.10 in.) long and more than 5.1 mm (0.20 in.) away from the nearest delamination. 8.4 If the delamination observed at this point exceeds 5 %, the entire cycle is repeated once and the delamination observed and recorded at the end of the second cycle.
7. Procedure 7.1 Place the test specimens in the autoclave or pressure vessel and weight them down. Admit water at a temperature of 18 to 27°C (65 to 80°F) in sufficient quantity so that the specimens are completely submerged. Separate the specimens by stickers, wire screens, or other means in such a manner that all end grain surfaces are freely exposed to the water. Draw a vacuum of 508 to 635 mm (20 to 25 in.) Hg (at sea level) and hold it for 5 min. Then release the vacuum and apply a pressure of 517 + 34 kPa (756 5 psi) for 1 h. With the specimens still completely immersed, repeat this vacuum pressure cycle making a two-cycle impregnating period requiring a total of 2 1 ⁄ 6 h. Dry the specimens for a period of between 21 and 22 h at 64 to 67°C (147 to 153°F) and a relative humidity not greater than 2
D 1101 9. Calculation and Report
the necessary resources have not been forthcoming.
9.1 Express the total length of open adhesive joints on the two end-grain surfaces of each specimen as a percentage of the entire length of the adhesive joints exposed on these surfaces (except omit bond lines at knots and knotty areas). Report this value as the percentage delamination of the specimen.
11. Keywords 11.1 exterior use; glulam; laminated wood; structural-gluedlaminated timber; structural laminated wood
10. Precision and Bias 10.1 No precision and bias exist for these test methods, as The American Society for Testing and Materials takes no position respecting the validity of any patent rights asserted in connection with any item mentioned in this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the risk of infringement of such rights, are entirely their own responsibility. This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years and if not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standards and should be addressed to ASTM Headquarters. Your comments will receive careful consideration at a meeting of the responsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you should make your views known to the ASTM Committee on Standards, at the address shown below. This standard is copyrighted by ASTM, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the above address or at 610-832-9585 (phone), 610-832-9555 (fax), or
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